It's been 15 years since George Clooney became a breakout star thanks to NBC's (then) megahit ER. As executive producer John Wells makes final preparations to finally close the doors of County, and other original stars (such as Anthony Edwards in his role of Dr. Mark Greene) do valedictory laps of their own, the question remains: Could Clooney come back?

Wells just updated us on where negotiations stand, and there's one last element that could make it happen...

According to Wells, "George is very busy, he's very handsome...[and] we've talked about [him coming back] a couple of times. It's George. We'll be shooting down there at the end, and if he comes by and says he wants to do something, he'll do it."

So what's that last element? "George loves practical jokes," says Wells, "so who knows." Basically, if George Clooney was on a kick one day, it could happen. Gotta love the idea of Clooney rolling up to the gates at Warner Brothers and telling the guard he's reporting for duty on ER
NBC just picked up three more episodes of ER, as well as a new John Wells drama called Southland. The show, formerly titled LAPD and then Police, stars Ben McKenzie and Michael Cudlitz (as well as many other familiar TV faces) as Los Angeles-area cops on the beat.

You can catch the two-hour series finale of ER (with or without Clooney) April 2 at 9 p.m. Southland premieres the following Thursday, April 9, at 10 p.m., taking over the slot ER miraculously held for 15 years running.

Do you think Clooney will do it? Do you think the ER crew could turn on a dime and produce a Clooney scene or episode on short notice? Would you want that? And what other ER alums are you waiting to see?